The present invention generally relates to electrical switches and, more particularly, to a multi-function stalk switch.
There is a need to provide a plurality of control switches that are easily accessible to a stationary operator in the field of motor vehicles, where it is desirable to place all of the controls frequently needed by an operator of the motor vehicle in such a position that they may be manipulated with a minimum of movement by the driver.
It is desirable to incorporate additional functionalities into the stalk switch traditionally used to activate the vehicle turn signals because of the stalk""s close proximity to the vehicle steering wheel. However, designers have encountered various problems relating to complexity, cost and reliability as the number of integrated functions increase.
There is therefore a need for a stalk switch capable of activating a multiplicity of functions while maintaining low complexity from an assembly standpoint, low cost and/or high reliability. The present invention is directed toward meeting this need.
The present invention relates to one or more of the following: A multi-function stalk switch that incorporates a pushbutton switch, a first rotary switch and a second rotary switch onto the end of a stalk, wherein further switching functions may be executed by moving the entire stalk in either of two orthogonal planes. The stalk switch incorporates many design features that enable it to be assembled at low cost from a small number of parts. One such feature may include the use of plastic-on-plastic detents to control positioning of the rotary switches so that they wipe across predetermined portions of a flexible printed circuit board. Another feature may include the inclusion of a spring-loaded plunger detent riding in a concave centering mechanism that is operable to automatically return the stalk switch to its central (neutral) position after removal of external biasing forces. A further feature may include magnets on the stalk switch and Hall effect sensors fixedly mounted nearby in order to sense movement of the magnets (and therefore the stalk) in two orthogonal planes. Further features of the invention are also disclosed.
In one form of the invention, a multi-function switch is disclosed, comprising: a first rotary switch module having a first surface; at least one substantially incompressible first detent formed on said first surface; a rotary switch support member having a second surface; and at least one substantially incompressible second detent formed on said second surface; wherein said at least one first detent engages said at least one second detent; and wherein dimensions of said at least one first detent and said at least one second detent are such that said at least one first detent may be forced to override said at least one second detent when a first sufficient torquing force is applied to said first rotary switch module.
In another form of the invention, a multi-function switch is disclosed, comprising: a first rotary switch module having a first surface; a first conductive bridge contact coupled to said first surface; a rotary switch support member having a second surface; and a flexible circuit board in contact with and substantially conforming to at least a portion ofxe2x80x94said second surface, said flexible circuit board having a plurality of exposed conductive contacts; wherein said first conductive bridge contact is operable to conductively couple at least two of said contacts when said first rotary switch module is at a first position with respect to said rotary switch support member.
In another form of the invention, a switch stalk is disclosed, comprising: a handle stalk having a proximal end and a distal end, said proximal end being operatively coupled to said rotary switch support member; a plunger coupled to said stalk distal end such that said plunger may move linearly with respect to said stalk distal end, said plunger being biased in said distal direction; a rotational receptacle coupled to said handle stalk such that said handle stalk may pivot in at least one plane; and a concave centering mechanism having a concave surface and coupled to said rotational receptacle such that said plunger is in contact with said concave surface; wherein a pivoting force applied to the handle stalk causes said plunger to be displaced along said concave surface, thereby compressing said plunger away from said distal end; and wherein removal of said pivoting force allows distal linear movement of said plunger in response to said plunger bias, thereby forcing said plunger to a center of said concave surface.
In another form of the invention, a multi-function switch is disclosed, comprising: a handle stalk having a proximal end and a distal end, said proximal end being operatively coupled to said rotary switch support member; a rotation assembly coupled to said handle stalk such that said handle stalk may be rotated with respect to said rotation assembly in at least one plane; at least one magnet coupled to said handle stalk; and at least one magnetic field sensor, wherein said at least one magnetic field sensor is positioned to sense movement of said at least one magnet when said handle stalk is rotated.
In another form of the invention, a multi-function switch is disclosed, comprising: a first rotary switch module having a first surface, a rotary switch support member having a second surface, at least one first detent formed on one of said first and second surfaces, a first detent washer shaped to engage said at least one first detent, and having an angular position fixed relative to one of the first rotary switch module and the rotary switch support member, and a first spring positioned to bias said first detent washer against said at least one first detent.
In another form of the invention, a multi-function switch is disclosed, comprising: a first rotary switch module having a first surface, a first magnet coupled to said first rotary switch module, a second rotary switch module having a third surface, a second magnet coupled to said second rotary switch module, a rotary switch support member having a second surface and a fourth surface, at least one first detent formed on one of said first and second surfaces, at least one second detent formed on one of said third and fourth surfaces, a first detent washer shaped to engage said at least one first detent and having an angular position fixed relative to one of the first rotary switch module and the rotary switch support member, a second detent washer shaped to engage said at least one second detent and having an angular position fixed relative to one of the second rotary switch module and the rotary switch support member. The stalk switch further comprises a first spring positioned to bias said first detent washer against said at least one first detent and a second spring positioned to bias said second detent washer against said at least one second detent. The multi-function stalk switch further comprises a flexible circuit board in contact with and substantially conforming to at least a portion of said second surface, said flexible circuit board having a first plurality of first magnetic field sensors, wherein said first magnet is positioned to be detected by at least one of said plurality of magnetic field sensors when said first rotary switch module is at a first position with respect to said rotary switch support member; and wherein said second magnet is positioned to be detected by at least one of said plurality of magnetic field sensors when said first rotary switch module is at a second position with respect to said rotary switch support member. The stalk switch further comprises a handle stalk having a proximal end and a distal end, said proximal end being operatively coupled to said rotary switch support member, and said distal end having a plunger coupled thereto such that said plunger may move linearly with respect to said stalk distal end, said plunger being biased in said distal direction, a rotation assembly coupled to said handle stalk by means of a first pivot pin extending therethrough, such that said handle stalk can rotate in a first plane, and by a second pivot pin, such that said handle stalk can rotate in a second plane, said second plane being substantially perpendicular to said first plane, a rotational receptacle coupled to said rotation assembly and having a first hole and a second hole, a concave centering mechanism having a concave surface and coupled to said rotational receptacle such that said plunger is in contact with said concave surface, wherein a pivoting force applied to the handle stalk causes said plunger to be displaced along said concave surface, thereby compressing said plunger away from said distal end, and wherein removal of said pivoting force allows distal linear movement of said plunger in response to said plunger bias, thereby forcing said plunger to a center of said concave surface. The stalk switch further comprises first and second plungers having respective first and second enlarged heads and being positioned substantially within said first hole and said second hole, respectively, a proximal third magnet substantially positioned within said first plunger and coupled to said handle stalk proximal of said first pivot pin, a distal third magnet coupled to said handle stalk distal to said first pivot pin positioned substantially within said second plunger, a fourth spring positioned around said first plunger between said first enlarged head and said rotation assembly, thereby biasing said first plunger away from said rotation assembly, a fifth spring positioned around said second plunger between said second enlarged head and said rotation assembly, thereby biasing said second plunger away from said rotation assembly, at least one second Hall effect sensor for sensing motion of said third magnets caused by rotation of said handle stalk about said first pivot pin, and at least one third Hall effect sensor for sensing rotation of said handle stalk about said second pivot pin.